To find all effectors in the scene, we need to loop over all objects.
Doing this during depsgraph evaluation caused crashes because not all
objects are guaranteed to be evaluated yet.
To fix this, we now cache the relations as part of the dependency graph
build. As a bonus this also makes evaluation faster for big scenes,
since looping over all objects for each particle system is slow.
Fixes T55156.
OVERVIEW
* In 2.7 terminology, all layers and groups are now collection datablocks.
* These collections are nestable, linkable, instanceable, overrideable, ..
which opens up new ways to set up scenes and link + override data.
* Viewport/render visibility and selectability are now a part of the collection
and shared across all view layers and linkable.
* View layers define which subset of the scene collection hierarchy is excluded
for each. For many workflows one view layer can be used, these are more of an
advanced feature now.
OUTLINER
* The outliner now has a "View Layer" display mode instead of "Collections",
which can display the collections and/or objects in the view layer.
* In this display mode, collections can be excluded with the right click menu.
These will then be greyed out and their objects will be excluded.
* To view collections not linked to any scene, the "Blender File" display mode
can be used, with the new filtering option to just see Colleciton datablocks.
* The outliner right click menus for collections and objects were reorganized.
* Drag and drop still needs to be improved. Like before, dragging the icon or
text gives different results, we'll unify this later.
LINKING AND OVERRIDES
* Collections can now be linked into the scene without creating an instance,
with the link/append operator or from the collections view in the outliner.
* Collections can get static overrides with the right click menu in the outliner,
but this is rather unreliable and not clearly communicated at the moment.
* We still need to improve the make override operator to turn collection instances
into collections with overrides directly in the scene.
PERFORMANCE
* We tried to make performance not worse than before and improve it in some
cases. The main thing that's still a bit slower is multiple scenes, we have to
change the layer syncing to only updated affected scenes.
* Collections keep a list of their parent collections for faster incremental
updates in syncing and caching.
* View layer bases are now in a object -> base hash to avoid quadratic time
lookups internally and in API functions like visible_get().
VERSIONING
* Compatibility with 2.7 files should be improved due to the new visibility
controls. Of course users may not want to set up their scenes differently
now to avoid having separate layers and groups.
* Compatibility with 2.8 is mostly there, and was tested on Eevee demo and Hero
files. There's a few things which are know to be not quite compatible, like
nested layer collections inside groups.
* The versioning code for 2.8 files is quite complicated, and isolated behind
#ifdef so it can be removed at the end of the release cycle.
KNOWN ISSUES
* The G-key group operators in the 3D viewport were left mostly as is, they
need to be modified still to fit better.
* Same for the groups panel in the object properties. This needs to be updated
still, or perhaps replaced by something better.
* Collections must all have a unique name. Less restrictive namespacing is to
be done later, we'll have to see how important this is as all objects within
the collections must also have a unique name anyway.
* Full scene copy and delete scene are exactly doing the right thing yet.
Differential Revision: https://developer.blender.org/D3383https://code.blender.org/2018/05/collections-and-groups/
The depsgraph was always created within a fixed evaluation context. Passing
both risks the depsgraph and evaluation context not matching, and it
complicates the Python API where we'd have to expose both which is not so
easy to understand.
This also removes the global evaluation context in main, which assumed there
to be a single active scene and view layer.
Differential Revision: https://developer.blender.org/D3152
2.8x branch added bContext arg in many places,
pass eval-context instead since its not simple to reason about what
what nested functions do when they can access and change almost anything.
Also use const to prevent unexpected modifications.
This fixes crash loading files with shadows,
since off-screen buffers use a NULL context for rendering.
Note that some little parts of code have been dissabled because eval_ctx
was not available there. This should be resolved once DerivedMesh is
replaced.
This reverts commit 5aa19be912 and b4a721af69.
Due to postponement of particle system rewrite it was decided to put particle code
back into the 2.8 branch for the time being.
In addition to pack of conflicts listed below, also had to comment out particle part of new Alembic code... :/
Conflicts:
intern/ghost/intern/GHOST_WindowWin32.cpp
source/blender/blenkernel/BKE_effect.h
source/blender/blenkernel/BKE_pointcache.h
source/blender/blenkernel/intern/cloth.c
source/blender/blenkernel/intern/depsgraph.c
source/blender/blenkernel/intern/dynamicpaint.c
source/blender/blenkernel/intern/effect.c
source/blender/blenkernel/intern/particle_system.c
source/blender/blenkernel/intern/pointcache.c
source/blender/blenkernel/intern/rigidbody.c
source/blender/blenkernel/intern/smoke.c
source/blender/blenkernel/intern/softbody.c
source/blender/depsgraph/intern/builder/deg_builder_relations.cc
source/blender/gpu/intern/gpu_debug.c
source/blender/makesdna/DNA_object_types.h
source/blender/makesrna/intern/rna_particle.c
Current implementation more or less indiscriminately links physics
objects to colliders and forces, ignoring precise details of layer
checks and collider groups. The new depsgraph seemed to lack some
such links at all. The relevant code in modifiers suffers from a
lot of duplication.
Different physics simulations use independent implementations of
collision and similar things, which results in a lot of variance:
* Cloth collides with objects on same or visible layer with dupli.
* Softbody collides with objects on same layer without dupli.
* Non-hair particles collide on same layer with dupli.
* Smoke uses same code as cloth, but needs different modifier.
* Dynamic paint "collides" with brushes on any layer without dupli.
Force fields with absorption also imply dependency on colliders:
* For most systems, colliders are selected from same layer as field.
* For non-hair particles, it uses the same exact set as the particles.
As a special quirk, smoke ignores smoke flow force fields; on the other
hand dependency on such field implies dependency on the smoke domain.
This introduces two utility functions each for old and new depsgraph
that are flexible enough to handle all these variations, and uses them
to handle particles, cloth, smoke, softbody and dynpaint.
One thing to watch out for is that depsgraph code shouldn't rely on
any properties that don't cause a graph rebuild when changed. This
was violated in the original code that was building force field links,
while taking zero field weights into account.
This change may cause new dependency cycles in cases where necessary
dependencies were missing, but may also remove cycles in situations
where unnecessary links were previously created. It's also now possible
to solve some cycles by switching to explicit groups, since they are
now properly taken into account for dependencies.
Differential Revision: https://developer.blender.org/D2141
This way it doesn't have to be stored as DNA runtime pointers or passed
down as a function argument. Currently there is now no property or
button to enable debugging, this will be added again later.
to support multiple hash identifiers.
Using explicit hashing functions for every sim debug call defeats the
purpose of having a quick feedback system. Now this can be done simply
by passing an arbitrary number of hash inputs (integers) at the end of
the function calls, which are then combined by a system of variadic
macros (based on the ELEM feature). Up to 8 identifiers are supported
currently, but more could be added easily if needed.
Conflicts:
source/blender/blenkernel/intern/particle_system.c
source/blender/physics/intern/BPH_mass_spring.cpp
This implements a penalty force as well as a repulsion force to avoid
further penetration, as suggested in
"Simulating Complex Hair with Robust Collision Handling"
(http://graphics.snu.ac.kr/publications/2005-choe-HairSim/Choe_2005_SCA.pdf)
Friction forces are still missing. More problematic is handling of
moving colliders, when face swap places with the hair vertex and a
collision is missed, putting the vertex inside the mesh volume. Larger
margins might help, but ultimately using Bullet collision detection is
probably more reliable and failsafe.
as forces, velocities, contact points etc.
This uses a hash table to store debug elements (dots, lines, vectors at
this point). The hash table allows continuous display of elements that
are generated only in certain time steps, e.g. contact points, while
avoiding massive memory allocation. In any case, this system is really
a development feature, but very helpful in finding issues with the
internal solver data.
updates.
This file crashes on loading with NULL pointer access to curve_cache:
{F77132}
The pdInitEffectors function was amalgamating the simple
collection of effector objects with an automatic precalculation for
curve guides and the like. This precalculation requires object data
that may not be available until the DAG has finished.
Since for DAG dependencies only the list of effectors is required,
added an argument to disable precalculation when collecting effectors.
added some missing functions too - which are not used yep but should be there for api completeness.
* CDDM_set_mloop
* CDDM_set_mpoly
* BLI_mempool_count
* where_is_object_time was called for every effector evaluation only to determine the object velocity in some rare cases.
* Calculating the effector velocity is now done in the effector precalculation stage.
* Removing this makes the code thread safe and also should give some nice performance boosts when simulating a lot of points.
* Thanks to MiikaH for noticing this problem.
The goodies:
* Curves can be used as normal dynamic effectors too with
the new "curve" field shape.
* Group visualization has optional duplication counts for
each object in the specified group.
* Object & group visualizations, which are done without
taking the dupliobject's global position into account
(unless the whole group is used). This is much nicer than
the previous behavior, but I added a "Use Global Location"
option for those who want to use it the old way.
* The active particle system's particles are now drawn a
with theme coloured outline instead of pure white.
* Added object aligned velocity factors (buttons categorized
and re-organized too).
Bug fixes:
* Absorption didn't work as the ui toggle button was forgotten.
* Some other force field ui tweaks.
* Crash after adding children and changing trails count.
* Display types "cross" and "axis" crashed.
* Particles weren't drawn with correct coloring.
* Billboards didn't update properly in viewport to camera
location changes.
* Particle rotation wasn't recreated correctly from point cache.
* Changing particles amount crashed sometimes.
* Some files with child hair crashed on loading.
* Compiler warning fixes.
* Adding boids crashed on frame 1;
* Unified scene wide gravity (currently in scene buttons)
instead of each simulation having it's own gravity.
* Weight parameters for all effectors and an effector group
setting.
* Every effector can use noise.
* Most effectors have "shapes" point, plane, surface, every point.
- "Point" is most like the old effectors and uses the
effector location as the effector point.
- "Plane" uses the closest point on effectors local xy-plane
as the effector point.
- "Surface" uses the closest point on an effector object's
surface as the effector point.
- "Every Point" uses every point in a mesh effector object
as an effector point.
- The falloff is calculated from this point, so for example
with "surface" shape and "use only negative z axis" it's
possible to apply force only "inside" the effector object.
* Spherical effector is now renamed as "force" as it's no longer
just spherical.
* New effector parameter "flow", which makes the effector act as
surrounding air velocity, so the resulting force is
proportional to the velocity difference of the point and "air
velocity". For example a wind field with flow=1.0 results in
proper non-accelerating wind.
* New effector fields "turbulence", which creates nice random
flow paths, and "drag", which slows the points down.
* Much improved vortex field.
* Effectors can now effect particle rotation as well as location.
* Use full, or only positive/negative z-axis to apply force
(note. the z-axis is the surface normal in the case of
effector shape "surface")
* New "force field" submenu in add menu, which adds an empty
with the chosen effector (curve object for corve guides).
* Other dynamics should be quite easy to add to the effector
system too if wanted.
* "Unified" doesn't mean that force fields give the exact same results for
particles, softbody & cloth, since their final effect depends on many external
factors, like for example the surface area of the effected faces.
Code changes
* Subversion bump for correct handling of global gravity.
* Separate ui py file for common dynamics stuff.
* Particle settings updating is flushed with it's id through
DAG_id_flush_update(..).
Known issues
* Curve guides don't yet have all ui buttons in place, but they
should work none the less.
* Hair dynamics don't yet respect force fields.
Other changes
* Particle emission defaults now to frames 1-200 with life of 50
frames to fill the whole default timeline.
* Many particles drawing related crashes fixed.
* Sometimes particles didn't update on first frame properly.
* Hair with object/group visualization didn't work properly.
* Memory leaks with PointCacheID lists (Genscher, remember to
free pidlists after use :).
All kinds of changes to get it ready for UI layouts. This means RNA
and operators should be working correct, but most buttons are still
not actually there yet.
* Added near empty soft body, fluid, field and collision panels,
tweaks to cloth panels.
* Fluid bake works, but without escape or showing any progress.
* Fluid/Softbody/Cloth/Collision can now be both added as modifiers
or in the physics panels.
* Missing: fields & soft body for particles.
* Missing: proper updating softbodies, guess this code still needs
updates after pointcache refactor?
Think global, act local!
The old favorite G.scene gone! Man... that took almost 2 days.
Also removed G.curscreen and G.edbo.
Not everything could get solved; here's some notes.
- modifiers now store current scene in ModifierData. This is not
meant for permanent, but it can probably stick there until we
cleaned the anim system and depsgraph to cope better with
timing issues.
- Game engine G.scene should become an argument for staring it.
Didn't solve this yet.
- Texture nodes should get scene cfra, but the current implementation
is too tightly wrapped to do it easily.
- For newtonian particles a "self effect" button in particle extras makes the particles be effected by themselves if a particle effector is defined for this system, currently this is a brute force method so things start getting slow with more than ~100 particles, but this will hopefully change in the future.
- Two new effector types: charge and a Lennard-Jones potential based force (inter-molecular forces for example).
-Charge is similar to spherical field except it changes behavior (attract/repulse) based on the effected particles charge field (negative/positive) like real particles with a charge.
-The Lennard-Jones field is a very short range force with a behavior determined by the sizes of the effector and effected particle. At a distance smaller than the combined sizes the field is very repulsive and after that distance it's attractive. It tries to keep the particles at an equilibrium distance from each other. Particles need to be at a close proximity to each other to be effected by this field at all.
- Particle systems can now have two effector fields (two slots in the fields panel). This allows to create particles which for example have both a charge and a Lennard-Jones potential.
Campbell Barton
Brecht Van Lommel
Luca Rood
Lukas Tönne
Dalai Felinto
Bastien Montagne
Alexander Gavrilov
Janne Karhu
Nathan Letwory
Brecht Van Lommel
Ton Roosendaal
Daniel Genrich
Chris Want